<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>行内样式表</title>
</head>
<body>
<p style="border-bottom: #66ccff 5px solid;color: red;font-size:40px">我是一行文字</p>
<!--style 属性的值就是css代码-->
</body>
</html>